A SO2 removal device for the purification of high-purity electronic-grade sulfuric acid

Abstract

This invention relates to an SO2 removal device for high-purity electronic-grade sulfuric acid purification, comprising: an SO2 removal assembly including an air inlet pipe sealed and rotatably mounted between the outer shell of the sulfuric acid purification tank and the bottom gap of the PTFE liner; a plurality of purge pipes with upward-facing air outlets connected to the outward-facing side wall of the air inlet pipe; and corresponding backflushing pipes horizontally connected to the bottom side of the purge pipes; an ultrapure air inlet assembly including an air filling pipe connected between the air inlet pipe and the PTFE liner; a waste acid collection assembly including an absorption tank storing industrial water; an exhaust pipe connected to the lower side of the absorption tank and connected to the top of the outer shell of the sulfuric acid purification tank; and a water circulation assembly including a circulation pump, the inlet and outlet of which are respectively connected to a water inlet pipe and a water outlet pipe located in the absorption tank. This invention can effectively and efficiently remove SO2 passing through the PTFE liner in real time under positive pressure purging, and can effectively ensure the absorption rate of the removed SO2.

Description

Technical Field

[0001] This invention relates to the field of purification technology in the preparation process of electronic-grade sulfuric acid, specifically to an SO2 removal device for the purification of high-purity electronic-grade sulfuric acid. Under positive pressure purging, it can remove SO2 passing through the PTFE liner in real time by replacing it with CDA, and can effectively ensure the absorption rate of SO2 after replacement removal. Background Technology

[0002] Currently, high-purity electronic-grade sulfuric acid is often purified using liquid SO3. In the process of sulfuric acid production, SO2 is converted into SO3 through a catalytic converter (vanadium pentoxide). After the SO3 is absorbed by sulfuric acid, water is added and absorbed in the PTFE lining material of the sulfuric acid purification tank to obtain electronic-grade sulfuric acid.

[0003] The conversion of SO2 to SO3 is not 100% complete; sulfuric acid contains free SO2, which can easily pass through the PTFE lining and combine with moisture in the air to form acid. Since the outer structure of sulfuric acid purification tanks is generally made of stainless steel, the acid formed from SO2 will corrode the stainless steel. Firstly, this can easily cause bulging and deformation of the lining welds, leading to lining damage. Secondly, SO2 corrosion of stainless steel will carry out metal ions, which will pass through the PTFE lining and affect the purity of the chemicals. Thirdly, bulging and deformation of the lining welds can easily cause SO3 or sulfuric acid leakage, leading to production safety accidents. Furthermore, the positive pressure exhaust method is prone to creating exhaust dead zones, resulting in the SO2 removal rate failing to meet design requirements. To remove SO2 passing through PTFE liners, some manufacturers are now using negative pressure exhaust to remove the SO2 with CDA (ultra-pure air) and then transfer it to an absorption tank where industrial water absorbs the SO2. The SO2-absorbed wastewater is then returned to the fuming acid treatment process for further absorption. While negative pressure exhaust can improve SO2 removal rates, it also increases the load on the outer structure of the sulfuric acid purification tank and the PTFE lining, which is clearly unsuitable for modern chemical production.

[0004] Therefore, the research objective of this invention is to design a high-purity electronic-grade sulfuric acid purification SO2 removal device that can effectively remove SO2 passing through the PTFE liner in real time under positive pressure purging, and can effectively ensure the absorption rate of SO2 after replacement removal, thereby effectively preventing SO2 from contaminating the purity of chemicals. Summary of the Invention

[0005] To address the technical problems existing in the prior art, the present invention provides an SO2 removal device for the purification of high-purity electronic-grade sulfuric acid, which can effectively solve the technical problems existing in the prior art.

[0006] The technical solution of this invention is: A device for removing SO2 during the purification of high-purity electronic-grade sulfuric acid includes: The SO2 removal assembly includes an air inlet pipe that is rotatably and sealed between the outer shell and the bottom of the PTFE liner of the corresponding sulfuric acid purification tank. The air inlet pipe is rotatably and sealed at the bottom center of the PTFE liner, and the side wall of the air inlet pipe is connected to a plurality of purge pipes with upward-facing air outlets. The outlet of the purge pipe is constricted and upward-facing, and the bottom side of the purge pipe is horizontally connected to a corresponding backflushing pipe with a constricted opening. An ultrapure air intake assembly includes an inflation pipe connected between the intake pipe and the PTFE liner, wherein the inflation pipe is connected to an external ultrapure air source via a corresponding exhaust fan; Waste acid collection assembly includes an absorption tank containing industrial water, and an exhaust pipe connected to the lower side of the absorption tank is provided on the top of the outer shell of the sulfuric acid purification tank. The water circulation assembly includes a circulation pump. The inlet and outlet ends of the circulation pump are respectively connected to an inlet pipe and a drain pipe located in the absorption tank. A corresponding driven pipe is rotatably installed at the drain end of the drain pipe. Several corresponding impeller blades are evenly distributed and fixed to the inner side of the driven pipe, and several corresponding cross-cutting plates are evenly distributed and fixed to the outer side of the driven pipe. The outlet end of the exhaust pipe is connected to an annularly arranged air guide groove, and the outer ends of the cross-cutting plates extend into the air guide groove.

[0007] The circulating pump is started to circulate and pump the industrial water in the absorption tank. When the industrial water is discharged through the drain end of the drain pipe, it generates a driving force on the impeller blades, which drives the driven pipe and the cross-cutting plate to rotate and disperse the gas discharged from the exhaust pipe.

[0008] The inlet end of the water inlet pipe is connected to a corresponding annular box. The inner side of the annular box is provided with a corresponding inlet in a linear shape. The inlet of the annular box is located on the upper outer periphery of the air guide groove. When the circulation pump is started to circulate and pump the industrial water in the absorption water tank, the industrial water is pumped away through the inlet of the annular box.

[0009] The upper part of the absorption tank is equipped with an overflow pipe connected to the corresponding sulfuric acid waste tank.

[0010] The absorption tank is equipped with a water inlet pipe that is connected to an external industrial water source. A corresponding siphon tee is connected to the drain pipe. The outlet of the water inlet pipe is connected to the siphon section of the siphon tee through a corresponding automatic valve.

[0011] The absorption tank is equipped with a pH meter. When the pH meter detects that the pH value of the industrial water is lower than the set value, the automatic valve opens, and external industrial water is replenished into the absorption tank under the siphon effect. The industrial water with the pH value reaching the set value overflows into the sulfuric acid waste tank through the overflow pipe.

[0012] A corresponding isolation plate is installed on the bottom side of the gas guide channel. A guide hole corresponding to the position of the driven pipe is provided in the middle of the isolation plate. The pH meter is installed in the absorption water tank below the isolation plate.

[0013] A corresponding float valve is installed at the feed end of the overflow pipe.

[0014] At least one corresponding abutting ball is mounted downwards at the lower middle part of the purge tube, and the abutting ball rolls against the bottom side of the outer shell of the sulfuric acid purification tank.

[0015] The air inlet pipe is rotatably mounted at the bottom center of the PTFE liner via a set of high and low sealed bearings, and the air outlet of the inflation pipe is connected to the air inlet pipe between the set of sealed bearings.

[0016] Compared with the prior art, the advantages and positive effects of the present invention are as follows: 1) The SO2 removal assembly of the present invention includes an air inlet pipe that is rotatably and sealed between the outer shell of the sulfuric acid purification tank and the bottom gap of the PTFE liner. The air inlet pipe is rotatably and sealed at the middle position of the bottom of the PTFE liner, and a plurality of purge pipes with upward-facing air blowing ports are connected to the side wall of the air inlet pipe. The outlet of the purge pipe is constricted and upward-facing, and a corresponding backflushing pipe is horizontally connected to the bottom side of the purge pipe. The opening of the backflushing pipe is constricted. During SO2 removal, the exhaust fan is activated to draw ultrapure air from the outside into the inlet pipe, and then pressurizes it before outputting it along the purge pipe. Simultaneously, some of the ultrapure air is pressurized through the backflushing pipe and output, which backflushes to drive the inlet pipe and purge pipe to rotate continuously, thereby removing SO2 from the area between the outer shell and the PTFE lining of the sulfuric acid purification tank without any blind spots. The ultrapure air output after being pressurized through the backflushing pipe not only backflushes the inlet pipe and purge pipe, but also removes SO2 from the area below the purge pipe, thus helping to ensure that SO2 is completely removed from the area between the outer shell and the PTFE lining of the sulfuric acid purification tank.

[0017] 2) Based on the waste acid collection component, the present invention further includes a water circulation component, which includes a circulation pump. The inlet and outlet of the circulation pump are respectively connected to an inlet pipe and a drain pipe located in the absorption tank of the waste acid collection component. A driven pipe is rotatably installed at the drain end of the drain pipe. Several corresponding impeller blades are evenly fixed to the inner side of the driven pipe, and several corresponding cross-cutting plates are evenly fixed to the outer side of the driven pipe. Most importantly, the exhaust end of the exhaust pipe is connected to a ring-shaped air guide groove, and the outer ends of the cross-cutting plates extend into the air guide groove. The continuous pumping of the circulating pump keeps the industrial water in the absorption tank in a flowing state, thereby increasing its contact rate with the SO2-containing exhaust gas and improving the SO2 absorption rate. During this process, the circulating industrial water also drives the impeller blades in the driven pipe, causing the driven pipe and the cross-cutting plate to rotate. When the SO2-containing exhaust gas is discharged through the exhaust pipe, the rotating cross-cutting plate effectively agitates and disperses it, causing most of it to be dispersed around the annularly arranged air guide groove. This prevents the SO2-containing exhaust gas from forming large bubbles that rise rapidly, significantly increasing the contact time and contact rate between the SO2 in the exhaust gas and the flowing industrial water. This effectively ensures the absorption rate of SO2 after replacement and removal, thus effectively preventing SO2 from contaminating the purity of chemicals and effectively avoiding equipment damage due to acid corrosion.

[0018] 3) The inlet end of the water inlet pipe of the present invention is connected to a corresponding annular box. The inner side of the annular box has a corresponding inlet in a linear pattern. The inlet of the annular box is located on the upper outer periphery of the gas guide groove. When the circulating pump starts to circulate and pump the industrial water in the absorption tank, the industrial water is pumped away through the inlet of the annular box. This creates a transverse water flow outside the path of the rising exhaust gas, thereby helping to slow down the rising rate of the exhaust gas and increase the contact rate between the industrial water and the exhaust gas, thus effectively further enhancing the absorption rate of SO2 after displacement removal.

[0019] 4) The absorption tank of this invention is equipped with a water inlet pipe connected to an external industrial water source, and a siphon tee pipe connected to the outlet pipe. The outlet of the water inlet pipe is connected to the siphon section of the siphon tee pipe via a corresponding automatic valve. When the pH meter detects that the pH value of the industrial water is lower than the set value, the automatic valve opens, and the external industrial water is replenished into the absorption tank under the siphon effect. The industrial water with the set pH value overflows into the sulfuric acid waste tank through the overflow pipe. This allows the replenished industrial water to be directly siphoned and mixed into the circulating water body, thereby improving the mixing rate between the newly replenished water and the existing water body.

[0020] 5) The bottom side of the gas guide channel of the present invention is sealed with an isolation plate, and the middle of the isolation plate is provided with a guide hole corresponding to the position of the driven pipe. The pH meter is installed in the absorption water tank below the isolation plate. This ensures that the newly added industrial water can be effectively and fully mixed with the bottom side of the original water body, thereby preventing the newly added industrial water from overflowing and being discharged before it is fully mixed, thus effectively improving the utilization rate of industrial water.

[0021] 6) At least one abutting ball is rolled downward at the lower end of the middle part of the purge pipe of the present invention. The abutting ball rolls against the bottom side of the outer shell of the sulfuric acid purification tank to effectively provide stable support for the purge pipe during rotation, thereby effectively ensuring the operational stability of the SO2 removal component during rotation. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention.

[0023] Figure 2 This is a cross-sectional view of the present invention.

[0024] Figure 3 The assembly section view of SO2 components is removed.

[0025] Figure 4 This is a schematic diagram of a structure with an annular box connected to the water inlet pipe.

[0026] Figure 5 A schematic diagram of the SO2 removal component.

[0027] Figure 6 This is a schematic diagram of the water circulation component.

[0028] In the attached diagram: SO2 removal component 1, air inlet pipe 101, purge pipe 102, backflush pipe 103, sulfuric acid purification tank 2, outer shell 201, PTFE liner 202, ultrapure air intake component 3, air filling pipe 301, exhaust fan 302, ultrapure air source 303, waste acid collection component 4, absorption water tank 401, industrial water 402, exhaust pipe 5, water circulation component 6, circulation pump 601, water inlet pipe 602, drain pipe 603, driven pipe fitting 7, impeller blade 8, cross-section plate 9, air guide groove 10, annular box 11, liquid inlet 1101, sulfuric acid waste liquid tank 12, overflow pipe 13, water replenishment pipe 14, siphon tee pipe 15, pH meter 16, isolation plate 17, guide hole 1701, float valve 18, abutment ball 19, sealed bearing 20. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0030] refer to Figure 1-6 A device for removing SO2 during the purification of high-purity electronic-grade sulfuric acid, comprising: SO2 removal component 1 includes an air inlet pipe 101 that is rotatably and sealed between the bottom gap of the outer shell 201 and the PTFE liner 202 of the corresponding sulfuric acid purification tank 2. The air inlet pipe 101 is rotatably and sealed at the middle position of the bottom of the PTFE liner 202, and the side wall of the air inlet pipe 101 is connected to a plurality of purge pipes 102 with the air outlet facing upward. The air outlet of the purge pipe 102 is constricted and facing upward, and the bottom side of the purge pipe 102 is horizontally connected to a corresponding backflushing pipe 103, the opening of the backflushing pipe 103 being constricted. The ultrapure air intake assembly 3 includes an inflation pipe 301 connected between the intake pipe 101 and the PTFE liner 201. The inflation pipe 301 is connected to an external ultrapure air source 303 through a corresponding exhaust fan 302. Waste acid collection assembly 4 includes an absorption tank 401, which stores corresponding industrial water 402. The top of the outer shell 201 of the sulfuric acid purification tank 2 is connected to an exhaust pipe 5 that is connected to the lower side of the absorption tank 401. The water circulation assembly 6 includes a circulation pump 601. The inlet and outlet ends of the circulation pump 601 are respectively connected to an inlet pipe 602 and a drain pipe 603 located in the absorption tank 401. A corresponding driven pipe 7 is rotatably installed at the drain end of the drain pipe 603. Several corresponding impeller blades 8 are evenly fixed to the inner side of the driven pipe 7, and several corresponding cross-cutting plates 9 are evenly fixed to the outer side of the driven pipe 7. The exhaust end of the exhaust pipe 5 is connected to an annular air guide groove 10, and the outer ends of the cross-cutting plates 9 extend into the air guide groove 10.

[0031] The circulation pump 601 is started to circulate and pump the industrial water 402 in the absorption tank 401. When the industrial water 402 is discharged through the drain end of the drain pipe 603, it generates a driving force on the impeller blade 8, which drives the driven pipe 7 and the cross-cutting plate 9 to rotate and disperse the gas discharged from the exhaust pipe 5.

[0032] During SO2 removal, the exhaust fan 302 is activated to draw ultrapure air from the outside into the inlet pipe 101 and then pressurizes it before outputting it along the purge pipe 102. Simultaneously, a portion of the ultrapure air is pressurized and output through the backflushing pipe 103, which backflushes and drives the inlet pipe 101 and the purge pipe 102 to rotate continuously, thereby removing SO2 between the outer shell 201 and the PTFE liner 202 of the sulfuric acid purification tank 2 without any blind spots. The ultrapure air output after being pressurized through the backflushing pipe 103 can not only backflush and drive the inlet pipe 101 and the purge pipe 102, but also remove SO2 in the area below the purge pipe 102, thus helping to ensure that SO2 is completely removed between the outer shell 201 and the PTFE liner 202 of the sulfuric acid purification tank 2.

[0033] Based on the waste acid collection component 4, this invention further includes a water circulation component 6. The continuous pumping of the circulation pump 601 keeps the industrial water 402 in the absorption tank 401 in a flowing state, thereby increasing its contact rate with the SO2-containing exhaust gas and thus improving the SO2 absorption rate. During this process, the circulating industrial water 402 also drives the impeller 8 in the driven pipe 7, causing the driven pipe 7 and the cross-cutting plate 9 to rotate. When the SO2-containing exhaust gas is discharged through the exhaust pipe 5, the rotating cross-cutting plate 9 effectively agitates and disperses it, causing most of it to disperse around the annularly shaped air guide groove 10. This prevents the SO2-containing exhaust gas from forming large bubbles that rise rapidly, significantly increasing the contact time and contact rate between the SO2 in the exhaust gas and the flowing industrial water 402. This effectively ensures the absorption rate of SO2 after replacement removal, effectively preventing SO2 contamination of chemical purity and effectively avoiding equipment damage due to acid corrosion.

[0034] The inlet end of the water inlet pipe 602 is connected to a corresponding annular box 11. The inner side of the annular box 11 is provided with a corresponding liquid inlet 1101 in a linear shape. The liquid inlet 1101 of the annular box 11 is located on the upper outer periphery of the air guide groove 10. When the circulation pump 601 is started to circulate and pump the industrial water 402 in the absorption water tank 401, the industrial water 402 is pumped away through the liquid inlet 1101 of the annular box 11.

[0035] With the intervention of the annular box 11 with a linear liquid inlet 1101, a transverse water flow is formed outside the path of the exhaust gas, thereby helping to slow down the rise rate of the exhaust gas and increase the contact rate between the industrial water 402 and the exhaust gas, thus effectively further assisting in improving the absorption rate of SO2 after replacement removal.

[0036] An overflow pipe 13 connected to a corresponding sulfuric acid waste tank 12 is provided at the upper part of the absorption tank 401. A water inlet pipe 14 connected to an external industrial water source is provided inside the absorption tank 401. A corresponding siphon tee pipe 15 is connected to the drain pipe 603. The outlet of the water inlet pipe 14 is connected to the siphon section of the siphon tee pipe 15 through a corresponding automatic valve.

[0037] The absorption tank 401 is equipped with a corresponding pH meter 16. When the pH meter 16 detects that the pH value of the industrial water 402 is lower than the set value, the automatic valve opens and external industrial water is replenished into the absorption tank 401 under the siphon effect. The industrial water 402 with the pH value reaching the set value overflows into the sulfuric acid waste liquid tank 12 through the overflow pipe 13.

[0038] The absorption tank 401 of this invention is equipped with a water inlet pipe 14 connected to an external industrial water source, and a siphon tee pipe 15 connected to a drain pipe 603. The outlet of the water inlet pipe 14 is connected to the siphon section of the siphon tee pipe 15 via a corresponding automatic valve. When the pH meter 16 detects that the pH value of the industrial water 402 is lower than the set value, the automatic valve opens, and the external industrial water is replenished into the absorption tank 401 under the siphon effect, so that the industrial water 402 with the set pH value overflows into the sulfuric acid waste tank 12 through the overflow pipe 13. This allows the replenished industrial water to be directly siphoned and mixed into the circulating water body, thereby improving the mixing rate between the newly replenished water and the existing water body.

[0039] A corresponding isolation plate 17 is installed on the bottom side of the air guide channel 10. The middle part of the isolation plate 17 is provided with a guide hole 1701 corresponding to the position of the driven pipe 7. The pH meter 16 is installed in the absorption water tank 401 on the lower side of the isolation plate. A corresponding float valve 18 is installed at the feed end of the overflow pipe 13.

[0040] The isolation plate 17 ensures that the newly added industrial water can be effectively and fully mixed with the bottom of the original water body, thereby preventing the newly added industrial water from overflowing and being discharged before it is fully mixed, thus effectively improving the utilization rate of industrial water.

[0041] At least one corresponding abutment ball 19 is rolled downwards at the lower middle part of the purge pipe 102, and the abutment ball 19 rolls against the bottom side of the outer shell 201 of the sulfuric acid purification tank 2. This effectively provides stable support for the purge pipe 102 during rotation, thus effectively ensuring the operational stability of the SO2 removal component 1 during rotation.

[0042] The air inlet pipe 101 is rotatably mounted on the bottom center of the PTFE liner 202 via a set of high and low sealed bearings 20, and the air outlet of the inflation pipe 301 is connected to the air inlet pipe 101 between the set of sealed bearings 20.

[0043] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A device for removing SO2 during the purification of high-purity electronic-grade sulfuric acid, characterized in that, include: SO2 removal assembly (1) includes an air inlet pipe (101) that is rotatably and sealed between the outer shell (201) and the bottom gap of the PTFE liner (202) of the corresponding sulfuric acid purification tank (2). The air inlet pipe (101) is rotatably and sealed at the bottom middle position of the PTFE liner (202), and the side wall of the air inlet pipe (101) is connected to a plurality of purge pipes (102) with the air blowing ports facing upward. The outlet of the purge pipe (102) is constricted and facing upward, and the bottom side of the purge pipe (102) is horizontally connected to a corresponding backflushing pipe (103), the opening of the backflushing pipe (103) is constricted. The ultrapure air intake assembly (3) includes an inflation pipe (301) connected between the intake pipe (101) and the PTFE liner (201), and the inflation pipe (301) is connected to an external ultrapure air source (303) through a corresponding exhaust fan (302). Waste acid collection assembly (4) includes an absorption tank (401) containing industrial water (402), and an exhaust pipe (5) connected to the lower side of the absorption tank (401) is provided on the top of the outer shell (201) of the sulfuric acid purification tank (2). The water circulation assembly (6) includes a circulation pump (601). The inlet and outlet of the circulation pump (601) are respectively connected to an inlet pipe (602) and a drain pipe (603) located in the absorption tank (401). A corresponding driven pipe (7) is rotatably installed at the drain end of the drain pipe (603). Several corresponding impeller blades (8) are evenly fixed to the inner side of the driven pipe (7). Several corresponding cross-cutting plates (9) are evenly fixed to the outer side of the driven pipe (7). The outlet end of the exhaust pipe (5) is connected to a ring-shaped air guide groove (10). The outer ends of the cross-cutting plates (9) extend into the air guide groove (10).

2. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 1, characterized in that, The circulating pump (601) is started to circulate and pump the industrial water (402) in the absorption tank (401). When the industrial water (402) is discharged through the drain end of the drain pipe (603), it generates a driving force on the impeller (8) to drive the driven pipe (7) and the cross-cutting plate (9) to rotate and disperse the gas discharged from the exhaust pipe (5).

3. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 1, characterized in that, The inlet end of the water inlet pipe (602) is connected to a corresponding annular box (11). The inner side of the annular box (11) is provided with a corresponding inlet (1101) in a linear shape. The inlet (1101) of the annular box (11) is located on the upper outer periphery of the air guide groove (10). When the circulating pump (601) is started to circulate and pump the industrial water (402) in the absorption water tank (401), the industrial water (402) is pumped away through the inlet (1101) of the annular box (11).

4. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 1, characterized in that, The upper part of the absorption tank (401) is provided with an overflow pipe (13) connected to the corresponding sulfuric acid waste tank (12).

5. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 4, characterized in that, The absorption tank (401) is provided with a water supply pipe (14) whose inlet end is connected to an external industrial water source. A corresponding siphon tee pipe (15) is connected to the drain pipe (603). The outlet end of the water supply pipe (14) is connected to the siphon section of the siphon tee pipe (15) through a corresponding automatic valve.

6. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 5, characterized in that, The absorption tank (401) is equipped with a corresponding pH meter (16). When the pH meter (16) detects that the pH value of the industrial water (402) is lower than the set value, the automatic valve opens and the external industrial water is replenished into the absorption tank (401) under the siphon effect. The industrial water (402) with the pH value reaching the set value overflows into the sulfuric acid waste liquid tank (12) through the overflow pipe (13).

7. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 6, characterized in that, A corresponding isolation plate (17) is installed on the bottom side of the air guide groove (10). The middle part of the isolation plate (17) is provided with a guide hole (1701) corresponding to the position of the driven pipe (7). The pH meter (16) is installed in the absorption water tank (401) on the lower side of the isolation plate.

8. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 4, characterized in that, A corresponding float valve (18) is installed at the feed end of the overflow pipe (13).

9. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 1, characterized in that, At least one corresponding abutting ball (19) is rolled downward at the lower middle part of the purge pipe (102), and the abutting ball (19) rolls against the bottom side of the outer shell (201) of the sulfuric acid purification tank (2).

10. The SO2 removal device for high-purity electronic-grade sulfuric acid purification according to claim 1, characterized in that, The air inlet pipe (101) is sealed and rotatably mounted on the bottom middle position of the PTFE liner (202) through a set of high and low sealed bearings (20), and the air outlet end of the air inlet pipe (301) is connected to the air inlet pipe (101) between the set of sealed bearings (20).

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